NEW YORK – In just a few years, new diabetes and weight loss drugs like Ozempic, Wegovy and Mounjaro have taken the world by storm. In the United States, one in eight adults say they have tried one of these drugs, known as GLP-1 drugs, and that number seems certain to increase as prices fall and new oral formulations come to market.
Fluffy and Fido may be next.
Okava Pharmaceuticals, a San Francisco-based biopharmaceutical company, announced Tuesday that it has formally begun a pilot study of GLP-1 in obese cats. The company is testing a new approach: Instead of receiving weekly injections of the drug, as is common in human patients, cats will receive small injectable implants, slightly larger than a microchip, that will release the drug slowly over a period of up to six months.
“You insert that capsule under the skin and come back six months later and the cat has lost weight,” said Chen Gaylor, the University of Florida veterinarian who is leading the study. “It’s like magic.”
The results are expected to appear next summer. If promising, they could represent the next frontier for a class of drugs that have disrupted human medicine and a potentially transformative treatment option for millions of pets.
Some veterinarians have already begun giving human GLP-1 medications, off-label, to diabetic cats, and Okava is not the only company developing a specific product for companion animals.
“I think it’s going to be the next big thing,” said Ernie Ward, a veterinarian and founder of the Pet Obesity Prevention Association. He added that veterinarians are “on the verge of a whole new era in obesity medicine.” He said Ward provided informal, unpaid advice to Okava and other companies interested in developing GLP-1 drugs for companion animals, but had no financial relationships with any of them.
However, the success of GLP-1 drugs in veterinary medicine is not predetermined. Experts said large clinical trials are needed, and it is not clear whether the drugs will be affordable, or even attractive to pet owners.
“For many people, the main way they interact with their pets and show their love often revolves around food,” said Marian Murphy, a veterinary nutritionist at the University of Tennessee.
Would pet owners pay for a drug that makes their animals eat less?
According to recent estimates, nearly 60 percent of the country’s dogs and cats are obese; Hundreds of thousands of them suffer from diabetes, Gaylor said. Experts agree that better treatments are urgently needed.
Diabetic pets typically need insulin injections twice a day, every day. It’s an expensive and labor-intensive treatment plan, and many pets are euthanized within a year of diagnosis, Gaylor said. “Diabetes is technically completely treatable,” he said. “And we’re doing a terrible job of treating it.”
As for obesity, which can significantly increase the risk of diabetes, especially in cats, insisting on diet and exercise has not been much better with pets than with humans. “We didn’t move the needle,” Ward said.
GLP-1 drugs are designed to mimic a hormone called glucagon-like peptide 1, which stimulates insulin production, slows digestion and promotes feelings of fullness. Some small studies suggest that the drugs could have similar benefits for both pets and people.
Scientists have found, for example, that some GLP-1 drugs intended for humans can also reduce appetite, improve glucose control, and cause weight loss in cats and dogs. (It may also cause known side effects, such as vomiting.)
“I see really clear benefits,” said Thomas Lutz, a veterinary physiologist at the University of Zurich, who has studied GLP-1 drugs. “I think what we’re really missing are large-scale clinical studies.”
However, the results were promising enough that some veterinarians began using human GLP-1 drugs off-label. Andrew Bugbee, a veterinary endocrinologist at Texas A&M University, said he uses these medications “several times a year” on diabetic cats.
But because veterinarians don’t have specific prescriptions, pet owners pay the same price as human patients, which is often hundreds of dollars a month. Existing medications don’t seem to work well enough to completely replace insulin in diabetic cats, especially those whose disease is at an advanced stage, Bugbee said.
He said that focusing on treating diabetic and obese pets may be a more effective approach, especially if companies can develop pet-specific products that are cheaper and easier for owners.
Okava is trying to create just that. “We believe that obesity, i.e. being overweight, is the number one preventive health problem in all areas of veterinary medicine,” said Michael Klotzman, the company’s founder and CEO.
Because a weekly injection would be too much for many pet owners, Okava teamed up with Vivani Medical, a biopharmaceutical company that has developed tiny subdermal implants that can be filled with a monthly supply of the GLP-1 drug.
Okava’s product, which contains a drug called exenatide, appeared to cause weight loss in healthy cats in a small proof-of-concept study.
The company is now evaluating the implants in obese cats in a larger, placebo-controlled study. (The study is called MEOW-1, meaning “Management of Overweight Cats.”) Okava hopes to enroll at least 50 cats, two-thirds of which will get the drug. Initially, researchers will follow the cats for three months; After that, owners will be able to choose a three-month extension.
If the results are promising, Okava plans to start a larger clinical trial next summer and apply for FDA approval within the next 18 to 24 months, Klotzman said.
Okava’s initial application to the FDA will focus on feline obesity, but the company also plans to study the drug’s effectiveness in dogs, and in various other conditions, such as diabetes and chronic kidney disease. (Human studies, many of which are still in their early stages, suggest the drug could have a wide range of health benefits.) Klotsman said he hopes the company can position the product as a life-extending medicine.
“Even if we get another year of healthy life — you know, if you take a dog for 10 to 11 years, it doesn’t seem like a lot, but that’s a 10 percent increase in life,” he said. “In this case, we think it’s not just an extra life. It’s going to be a healthier life.”
Ward said he is “optimistic” about the promise of GLP-1 drugs for companion animals, but studies like Okava’s are sorely needed. “Until we actually see it on the ground on a broader population, we won’t be able to draw conclusions,” he said. “That’s why it’s exciting that these companies are moving forward so quickly now.”
Biotechnology company ProLynx has also developed a long-acting GLP-1 drug that has shown potential in diabetic cats. ProLynx, which focuses primarily on human health, is now looking for an animal health company to help it continue developing the drug. “Initial interest appears to be very high,” said Robert Smith, a business development consultant at ProLynx.
To succeed in the veterinary market, developers will also have to confront some of the practical challenges associated with GLP-1 drugs, said Bethany Cummings, who studies GLP-1 on the UC Davis campus. One of the biggest challenges is “how to make it financially viable,” he noted.
Okava has committed to keeping the cost of its product no more than $100 a month, Klotzman said, noting that some pay more than that for luxury dog foods. “We think the market is there,” he added.
Additionally, treating diabetes is expensive in itself, Gaylor said. If GLP-1 drugs can prevent disease or put some diabetic pets into remission, it could save some owners money.
However, a medication that costs $100 a month will be out of reach for many pet owners, and even those who can afford it won’t have to rush out to buy it.
Some experts cite the case of Slentrol, an old weight-loss drug for dogs made by Pfizer’s animal health division (which later became a separate company called Zoetis). Slentrol, which was approved by the FDA in 2007, is not a GLP-1 drug, but it did effectively reduce dogs’ appetite.
Pet owners didn’t always like it. “They saw it as a negative side effect,” said Murphy, the veterinary nutritionist. “Because the main way they interacted with their pets was by feeding them, and seeing their joy and happiness when they ate the food.”
After a few years, the drug was discontinued.
Zoetis confirmed that it had not seen “sustained demand” for Silentrol, although it offered a different explanation. “We have found that pet owners often do not view their pet’s obesity as a medical condition that requires treatment,” Kevin Esch, senior vice president of global therapeutics, said in an emailed statement.
But Zoetis is exploring GLP-1 as a potential target for new treatments for diabetes in pets and other internal medical conditions, including heart disease, Esch said.
Murphy said he believes GLP-1 drugs have real potential in veterinary medicine, but as a supplement, not a replacement, to traditional weight management plans.
“I don’t think it’s going to be a simple, quick, easy solution, where you just give the medication and don’t have to worry about anything else,” he said.
Written by Emily Anthes